The present invention relates to a portable electric apparatus and an antenna device used for the apparatus. The portable electric apparatus comprises a digital radio tuner, an optical disc drive, and a casing containing therein the digital radio tuner and the optical disc drive. The digital radio tuner can receive radio waves from an artificial satellite (hereinafter, may be called “satellite waves”) and/or radio waves above ground (hereinafter, may be called “terrestrial waves”) by an antenna, for listening to digital radio broadcasting (may be merely called “radio broadcasting”). The optical disc drive can reproduce data recorded in an optical disc such as a CD (Compact Disc). The optical disc drive may not only reproduce data from the optical disc but also record data in the optical disc or record and reproduce data in/from the optical disc.
Recently, a digital radio receiver receiving the satellite waves and/or the terrestrial waves for listening to the digital radio broadcasting is developed and is put to practical use in USA. This kind of digital radio receiver can receive radio waves of approximately 2.33 GHz and can be used for listening to the radio broadcasting. Therein, the terrestrial waves are provided by slightly shifting the satellite waves in frequency after once receiving one by an earth station.
As the digital radio receiver, there is various types, such as a vehicle-mounted type, a stationary type stationed in house, and a portable type operated by battery.
As the digital radio receiver of the portable type, there is specifically a portable electric apparatus such as a portable audio apparatus containing an optical disc drive the CD, an amplifier, and speakers in addition to the digital radio tuner in a casing in an integrated fashion.
As an antenna capable of receiving the radio waves of the approximately 2.33 GHz, various types of antennas have been known. The antennas are classified broadly by configuration into a flat type (plain plate type) such as a patch antenna and a cylindrical type such as a loop antenna. The patch antenna or the loop antenna is generally provided for the portable electric apparatus separately from the casing. The antenna is connected to the radio tuner via a cable and a connector and used.
Japanese Patent Application Publication (JP-A) No. 2003-163521 discloses an electric apparatus comprising a patch antenna. The patch antenna is not for the digital radio broadcasting but may be usable for satellite waves.
The advantage of the portable electric apparatus is that is portable readily by the user and usable anywhere. However, the existing portable electric apparatus having the antenna separated from the casing as mentioned above is not necessarily sufficient in portability.